jackknife clam jackknife • jackknife-fish · · · Info · Definitions · Synonyms · Characters · · jackknife clam · · Text Common · · Latin · · Scripts 14 · · Length 3 · · Syllables Definitions · · · (noun) marine clam having a long narrow curved thin shell. Synonyms: razor clam, jackknife clam, knife-handle. · · Noun Definition 1 Synonyms · · · razor clam · · Synonym 1 knife-handle · · Synonym 2 Characters · · space U+0020 a latin small letter a U+0061 c latin small letter c U+0063 e latin small letter e U+0065 f latin small letter f U+0066 i latin small letter i U+0069 j latin small letter j U+006A k latin small letter k U+006B l latin small letter l U+006C m latin small letter m U+006D n latin small letter n U+006E